System for operating fire prevention devices

ABSTRACT

The system for operating fire prevention devices comprises a plurality of fire prevention device operators successively operated directly or through another already operated operator in response to the operation of one of the fire detectors. Each of the operators includes switch means for switching the circuit from one operator to another when the fire prevention device associated therewith completes its operation. The switch means also function to switch the circuit upon the failure of the fire prevention device within a predetermined time.

BACKGROUND OF THE INVENTION

This invention relates to systems for operating fire prevention devices,and more particularly to systems for operating a plurality of fireprevention devices such as fire shutters or smoke exhausting openingsupon a fire breakout.

It is required to quickly and automatically operate fire shutters orsmoke exhausting openings disposed in a building in response to theactuation of fire alarm equipment upon the fire breakout in order toprevent spreading of the fire site and to exhaust the smoke emitted fromthe fire. However, the conventional system with a plurality of fireprevention devices is arranged to simultaneously energize actuator coilswhich operate the fire prevention equipment. The actuator coils areconnected in parallel through a make contact of a local relay whichcloses in response to the operation of one of the fire detectorsdisposed in an appropriate area of the building. Therefore, the systemis required to have a large capacity electrical power source and thenumber and the size of the fire prevention devices, such as fireshutters and smoke exhausting openings, is limited.

Accordingly, the object of the present invention is to provide a systemfor operating fire prevention devices capable of operating asubstantially unlimited number of fire prevention devices with arelatively small capacity electrical power source.

Another object of the invention is to provide a system for operatingfire prevention devices operable in quick response to a fire breakout.

Still another object of the invention is to provide a system foroperating fire prevention devices reliable in operation.

DESCRIPTION OF THE DRAWINGS

The invention will now be described in detail in conjunction with thepreferred embodiments of the invention illustrated in the accompanyingdrawings in which:

FIG. 1 is a schematic circuit diagram of the system for operating fireprevention devices constructed in accordance with the present invention;and

FIGS. 2 to 4 are schematic circuit diagrams of modified systems foroperating fire prevention devices of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawing and in particular to FIG. 1, the system foroperating fire prevention devices of the invention comprises a receiverunit R, a detector unit D and an operator unit OP.

The receiver unit R comprises a suitable d.c. electric source E, withwhich a local relay N is connected in series through its make contact n₁and a resistor r. A flicker relay P is also connected in series with theelectric source E through a series-connected make contact n₂ of thelocal relay N and in parallel with the series circuit composed of thelocal relay N, the make contact n₁ and the resistor r. An indicationdevice, such as a lamp La in this embodiment, is connected in parallelwith the electric source E through a pair of parallel-connected makecontacts p and m. The contact p intermittently closes when the flickerrelay P is energized, and the contact m follows the open-and-closeoperation of a relay M which is connected to the electric source Ethrough a make contact n₃ of the local relay N and the operator unit OPcomposed of a plurality of operators OP₁, OP₂, . . . OP_(n) which willbe described in detail later for operating fire prevention devices (notillustrated). The indication lamp La may be replaced by any suitableindicator such as a buzzer, electric bell, etc.

The detector unit D comprises a plurality of fire detectors D₁, D₂ . . .D_(n) each including a detector element d₁, d₂ . . . or d_(n) andlocated at a suitable position in the area to be monitored such as theceiling of the building. The detectors D₁, D₂ . . . D_(n) are connectedin parallel with one another across the make contact n₁ and the resistorr.

The operator unit OP comprises a plurality of parallel-connected fireprevention device operators OP₁, OP₂ . . . OP_(n) connected across theelectric source E through the make contact n₃ of the relay N. All theoperators OP₁, OP₂ . . . OP_(n) are identical in construction and,therefore, only first operator OP₁ will be described hereinbelow. Thefirst fire prevention device operator OP₁ includes an actuator coil L₁which, when energized, initiates the operation of the associated fireprevention device such as a shutter or a smoke exhaust opening.Connected in series with the actuator coil L₁ is a limit switch SA₁which is switched from the first position (shown by a solid line) inwhich the actuator coil L₁ is energized through the first contact of thecoil L₁ to the second position (shown by a broken line) in which thecoil L₁ is deenergized and the coil L₂ in the next or second operatorOP₂ is energized through the second contact of the coil L₁ when theoperation of the fire prevention device is completed. Another switch orcontact t₁ is connected in series with the actuator coil L₁, and thecontact t₁ is adapted to switch, when a timer T₁ connected in parallelwith the actuator coil L₁ is operated, from the first position (shown bya solid line) in which the coil L₁ can be energized through the firstcontact of the contact t₁ to the second position (shown by a brokenline) in which the coil L₁ is deenergized and the actuator coil L₂ inthe second operator OP₂ is energized through the second contact of thecontact t₁. The operator OP₁ also comprises a limit switch SB₁ which isclosed when the fire prevention device associated with the operator OP₁is completely operated. The limit switches SB₁, SB₂ . . . SB_(n) areseries-connected to the electric source E through the relay M.

When one of the fire detectors D₁ - D_(n) detects the fire and closesits contact, the local relay N is energized and closes its make contactsn₁ - n₃. Therefore, with the relay N being self-held through the contactn₁, the flicker relay P intermittently operates to repeat theenergization and deenergization of the indication lamp La and the timerT₁ and the actuator coil L₁ of the first operator OP₁ are energizedthrough the switches SA₁ and t₁. The actuator coil L₁ then initiates theoperation of the fire prevention device by, for example, pulling out apin which otherwise holds the fire shutter or the closure member of thefire prevention device in the inoperative state, thereby allowing thefire shutter to be closed by any suitable means such as a door closer orallowing the damper of the smoke exhausting port to open by its ownweight.

When the fire prevention device associated with the operator OP₁ hascompletely closed, simultaneously with the closure of the switch SB₁,the limit switch SA₁ switches to the second position as shown by thebroken line in FIG. 1. This deenergizes the timer T₁ and the coil L₁and, at the same time, energizes the timer T₂ and the actuator coil L₂of the second operator OP₂.

This mode of operation is then successively repeated for each of thesecond to the nth operators OP₂, OP₃, . . . OP_(n) until all theoperators are operated. After they are all operated, the limit switchesSA₁, SA₂, . . . SA_(n) are all switched to the second position and thelimit switches SB₁, SB₂, . . . SB_(n) are all closed. Then the relay Mis operated to close its make contact m to cause the indication lamp Lawhich has been intermittently lit to be continuously energized,indicating that all the fire prevention device such as the shutters orthe smoke exhausting ports are operated.

If one or other of the fire prevention devices, for example the deviceassociated to the first operator OP₁, fails to operate for any reason,the limit switch SA₁ disposed in that first operator OP₁ does not switchto the second position. In that event, the timer T₁ actuates its switchcontact t from the first position to the second position after the lapseof a predetermined time period. This deenergizes the coil L₁ in thatfailed operator OP₁ and energizes the timer T₂ and the actuator coil L₂in the second operator OP₂.

Thus, according to the system for operating fire prevention devices ofthe present invention, each of the actuator coils L₁, L₂ . . . L_(n) ofthe operators OP₁, OP₂ . . . OP_(n), such as the fire shutters or thesmoke exhausting openings, is operated successively one by one and notsimultaneously. Therefore, the electric power source required foroperating the fire prevention device can be of smaller capacity thanthat required for the conventional system, and even with such a smallerpower source, the number and the size of the fire prevention devices isnot limited. Further, with the system of the present invention, even ifone or other of the fire prevention devices fails to operate for anyreason, all of the remaining prevention devices in the system can beoperated one by one, independently of the fire prevention device introuble.

Referring to FIG. 2, wherein another embodiment of the present inventionis illustrated, the receiver unit R and the operator unit OP of thisembodiment are the same as those illustrated in FIG. 1. All of the firedetectors D₁, D₂, . . . D_(n) are identical in construction andtherefore only the first detector D₁ will be described hereinbelow. Thedetector D₁ includes a detector element d₁ and a control relay A₁connected in series with the detector element d₁ . A make contact a'₁ ofthe control relay A₁ is connected across the detector element d₁, whilethe other make contact a₁ of the control relay A₁ is connected betweenthe electric source E and the limit switch SA₁ in parallel with the makecontact n₃ of the local relay N. In other respects, the detectors arethe same as those described in conjunction with FIG. 1.

With this circuit arrangement, when one of the fire detectors D_(n) forinstance detects the fire-breakout and closes its contact d₁, the localrelay N operates to close the contacts n₁ - n₃. This causes theindication lamp La to begin flickering, the operators OP₁ - OP_(n) ₋₁ tosuccessively operate, and causes the control relay A_(n) of the nthdetector D_(n) to close its contacts a'_(n) and a_(n), therebyself-holding the relay A_(n). Then, the operator OP_(n) of which limitswitch SA_(n) is connected to the contact a_(n) of the detector D_(n)operates to actuate the associated fire prevention device simultaneouslywith the operation of the first operator OP₁ which is carried out in thesame way as in the system shown in FIG. 1. In other respects, the systemoperates similarly to that shown in FIG. 1.

With this circuit arrangement, the fire prevention device locatedclosest to the fire site is first operated simultaneously with the firstoperator OP₁, providing quick and effective fire prevention.

FIG. 3 illustrates still another embodiment of the present invention, inwhich the receiver unit R, the fire detector unit D and the operatorunit OP themselves are identical to those shown in FIG. 2, only theconnection between the respective units being different. That is, theelectrical line and the make contact n₃ between the electric source Eand the limit switch SA₁ of the first operator OP₁ are omitted from thesystem shown in FIG. 2, and the normally-open second contact of thelimit switch SA_(n) in the nth operator OP_(n) is directly connected tothe circuit point between the contact a₁ of the detector D₁ and thelimit switch SA₁ of the first operator OP₁.

The circuit arrangement of this embodiment operates as follows: When oneof the fire detectors, the nth detector D_(n) for instance, detects thefire breakout and closes its contact d_(n), the local relay N actuatesto close its contacts n₁ and n₂, thereby causing the indication lamp Lato flicker similarly to the previous two embodiments. At the same time,the control relay A_(n) is also actuated to close its contacts a'_(n)and a_(n), with the control relay A_(n) being self-held, and the timerT_(n) and the actuator coil L_(n) of the operator OP_(n) are energizedto operate the fire prevention device, such as the fire shutter and thesmoke exhausting opening, associated with that operator OP_(n). Afterthe fire prevention device operated by the operator OP_(n) has completedits operation, the limit switch SA_(n) switches from the first positionto the second position to deenergize the timer T_(n) and the actuatorcoil L_(n) of the operator OP_(n) and, at the same time, to energize thetimer T₁ and the actuator coil L₁ of the first operator OP₁. Thisoperation of the operator is successively repeated one by one until allof the operators OP₁, OP₂, . . . OP_(n) complete their operations. Afterthis, the system operates identically to those described in conjunctionwith FIGS. 1 and 2.

FIG. 4 shows a circuit arrangement of still another embodiment of thepresent invention, which only differs from the embodiment shown in FIG.3 in that each of its operators OP₁, OP₂, . . . OP_(n) includes twodiodes b₁ and b₂. The diode b₁ of the second operator OP₂ is connectedbetween the junction between the second contact of the limit switch SA₂and the second contact of the contact t₂ and the limit switch of thesubsequent or third operator. The diode b₂ of the second operator OP₂ isconnected between the junction between the second contact of the limitswitch SA₂ and the second contact of the contact t₂ and the limit switchof the preceding or first operator OP₁. In other words, the junctionbetween the limit switch SA₂ and the contact t₂ is connected to thepreceding and the subsequent operators through the separate diodes b₁and b₂. Although the operators OP₁ and OP_(n) also include the diodes b₂and b₁, respectively, these diodes are not necessarily required for theproper operation of the system alone. These diodes may be left includedfor easy standardization of the operators, which allows the massproduction of the operators as the identical interchangeable components.

With this circuit arrangement, when one of the fire detector D₂ forinstance detects a fire breakout and closes its contact d₂, the localrelay N is operated to start the flickering of the indication lamp La.At the same time, the control relay A₂ also actuates its contacts a'₂and a₂ to self-hold the control relay A₂ as well as to energize thetimer T₂ and the actuator coil L₂ of the second operator OP₂, therebyactuating the fire prevention device, such as the fire shutter or thesmoke exhausting opening, adapted to be operated by that operator OP₂.After this fire prevention device is completely operated, the limitswitch SA₂ turns to the second position to deenergize the timer T₂ andthe actuator coil L₂ and, simultaneously, energize the timer T₁ and theactuator coil L₁ of the preceeding or first operator OP₁ through thediode b₂ as well as the timer and the actuator coil of the subsequent orthird operator through the diode b₁.

Thus, the operation of the fire prevention device starts from theoperator associated with the fire detector that first detects the firebreakout and then shifts towards both ends of the system one by one oneach side of the first operated operator until all the fire preventiondevices involved in the system are completely operated. As in theprevious embodiments, the indication lamp La is energized continuouslyafter the operation of all the fire prevention devices, and if any ofthe fire prevention devices fail to operate completely, the remainingsound devices can successfully be operated due to the function of thetimer T and its contact. This embodiment is preferable because itoperates the fire prevention device that is the closest to the fire siteand can operate the two neighbouring fire prevention devices on bothsides of of the first-operated operator at the same time, enabling thesystem to more quickly and effectively prevent spreading of the firesite.

What is claimed is:
 1. A system for operating fire prevention devicescomprising a plurality of fire prevention device operators eachcomprising an actuator coil adapted to be energized in response to theoperation of a fire detector directly or through another operator thathas already been operated, means for deenergizing said energizedactuator coil and energizing an actuator coil in another operator uponthe completion of the operation of said fire prevention deviceassociated with said energized actuator coil, means for deenergizingsaid energized actuator coil and energizing the actuator coil in saidother operator when said fire prevention device associated with saidenergized actuator coil fails to complete its operation within apredetermined time, and an indication device which intermittentlyoperates in response to the operation of said fire detectors and whichcontinuously operates when all of said fire prevention devices completetheir operations, said indication device operable by means disposed inthe respective fire prevention devices.
 2. A system for operating fireprevention devices comprising a plurality of fire prevention deviceoperators each comprising an actuator coil adapted to be energized inresponse to the operation of a fire detector directly or through anotheroperator that has already been operated, means for deenergizing saidenergized actuator coil and energizing an actuator coil in anotheroperator upon the completion of the operation of said fire preventiondevice associated with said energized actuator coil, means fordeenergizing said energized actuator coil and energizing the actuatorcoil in said other operator when said fire prevention device associatedwith said energized actuator coil fails to complete its operation withina predetermined time, an indication device which intermittently operatesin response to the operation of said fire detectors and whichcontinuously operates when all of said fire prevention devices completetheir operations, said indication device being an indication lampconnected to an electric source through a contact of a flicker relayoperable in response to the operation of the fire detectors through alocal relay and through a contact of a relay connected in parallel tosaid contact of said flicker relay and operable by series-connectedlimit switches each disposed in the respective fire prevention devices,said limit switches each including a contact adapted to be closed whensaid first prevention device completes its operation.